iommu/arm-smmu: fix programming of SMMU_CBn_TCR for stage 1

Stage-1 context banks do not have the SMMU_CBn_TCR[SL0] field since it
is only applicable to stage-2 context banks.

This patch ensures that we don't set the reserved TCR bits for stage-1
translations.

Cc: <stable@vger.kernel.org>
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 98fcd87..1f10ac0 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -843,8 +843,11 @@
 	reg |= TTBCR_EAE |
 	      (TTBCR_SH_IS << TTBCR_SH0_SHIFT) |
 	      (TTBCR_RGN_WBWA << TTBCR_ORGN0_SHIFT) |
-	      (TTBCR_RGN_WBWA << TTBCR_IRGN0_SHIFT) |
-	      (TTBCR_SL0_LVL_1 << TTBCR_SL0_SHIFT);
+	      (TTBCR_RGN_WBWA << TTBCR_IRGN0_SHIFT);
+
+	if (!stage1)
+		reg |= (TTBCR_SL0_LVL_1 << TTBCR_SL0_SHIFT);
+
 	writel_relaxed(reg, cb_base + ARM_SMMU_CB_TTBCR);
 
 	/* MAIR0 (stage-1 only) */